The present invention concerns a method of harvesting natural milk proteins by treating a fraction of the milk with a precipitant. This treatment separates the mixture into concentrated natural casein and a fraction that contains the precipitant.
Dividing milk into three fractions, specifically fat, casein, and whey, by centrifuging is known. Although all constituents of the milk can be considered nutrients, it has been impossible until now to process milk without some form of waste occurring. This situation has resulted in main products and byproducts with to some extent widely divergent physiological value and cost.
German Patent 555 273 suggests adding concentrated pectin to separate the milk into concentrated casein and pectin in whey. This approach made it possible for the first time to obtain a solution of natural casein at a sextuple concentration. The approach was not really successful, however, because it took so much pectin (approximately 250 kg/tonne of casein concentrate) and pectin is expensive. No one has been able to discover a way to exploit the whey that will recover the cost of the pectin.